Method and Apparatus for Realizing Application High Availability

1. A computer implemented method for realizing high availability of an application installed on a first node and a second node, the method comprising: determining whether an application is a high availability application based on an ID of the application; and performing a file replication process based on a determination that the application is a high availability application, the file replication process comprising: monitoring access operations to files by the application during execution of the application on the first node; and replicating a monitored update to a file by the application if the application performed an update to the file during the access operations, such replication being from the first node to a storage device accessible by the second node; sniffing execution of the application on the first node; and switching the application to, and initiating the application on, the second node in response to sniffing a failure in the execution of the application on the first node.

2. The method according to claim 1 , wherein, a first sub file system is created on the first node and a first dedicated block device is mounted on the first sub file system, and a second sub file system is created on the second node and a second dedicated block device is mounted on the second sub file system: wherein the replicating step includes replicating the updates in the first dedicated block device to the second dedicated block device; and wherein the method further comprises redirecting monitored updates to the file by the application to the first sub file system.

3. The method according to claim 2 , wherein replicating the updates in the first dedicated block device to the second dedicated block device is implemented by a disk operation hook that is hooked into the operating system, and wherein the hook is initiated whenever an update to a file is written into the first dedicated block device.

4. The method according to claim 2 , wherein redirecting monitored updates to the file by the application to the first sub file system comprises: copying the file from outside the first sub file system into the first sub file system in response to the first monitored update to a file outside the first sub file system; creating in the memory a file data structure of the file descriptor associated with the copy file in the first sub file system; and writing monitored updates to the file outside the first sub file system by the application to the copy file within the first sub file system by using the file data structure.

5. The method according to claim 1 , wherein the ID is a process ID of the application.

6. The method according to claim 1 , further comprising: registering, by the first node, the ID of the application in a registry in response to the application being initiated by a dedicated initiator; wherein determining whether the application is a high availability application includes: determining whether the ID of the application is in the registry in response to receiving a file access request from an application; and determining the application to be a high availability application based on determining the ID of the application is in the registry.

7. The method according to claim 2 , wherein monitoring access operations to files by the application and redirecting updates to the file by the application to the sub file system are implemented by a file operation hook that is hooked onto file access system calls of the operating system.

8. The method according to claim 2 , wherein: redirecting monitored updates to the file by the application to the first sub file system includes redirecting the monitored access operations to the file outside the first sub file system by the application to the first sub file system.

9. The method according to claim 1 , wherein a first sub file system is created on the first node and a storage device shared between the first node and the second node is mounted on the first sub file system, a second sub file system is created on the second node and the storage device is mounted on the second sub file system, and replicating the monitored updates to the file by the application from the active node to a storage device accessible to the passive node includes redirecting monitored updates to the file by the application to the first sub file system.

10. An apparatus for realizing high availability of an application installed on a first node and on a second node, the apparatus comprising: a redirecting module for determining whether the application is a high availability application based on an ID of the application; a monitoring module for monitoring access operations to files by the application during execution of the application on the first node; a replicating module for replicating, based on a determination that the application is a high availability application, the monitored updates to the file by the application from the first node to a storage device accessible to the second node based on the application updating the file during the access operations; a sniffing module for sniffing the execution of the application on the first node; and a switching and initiating module for switching the first node to the second node and initiating the application on the second node in response to sniffing a failure in the execution of the application on the first node.

11. An apparatus according to claim 10 , wherein, a first sub file system is created on the first node and a first dedicated block device is mounted on the first sub file system, and a second sub file system is created on the second node and a second dedicated block device is mounted on the second sub file system, the redirecting module redirects monitored updates to the file by the application to the first sub file system, and the replicating module replicates the updates in the first dedicated block device to the second dedicated block device.

12. The apparatus according to claim 11 , wherein the replicating module is implemented by a disk operation hook that is hooked into the operating system, and the hook is initiated whenever an update to a file is written into the first dedicated block device.

13. The apparatus according to claim 11 , wherein the redirecting module is responsive to the first monitored update to a file outside the first sub file system, to copy the file from outside the first sub file system into the first sub file system, and to create in the memory a file data structure of the file descriptor associated with the copy file in the first sub file system; and the redirecting module is configured to write monitored updates to the file outside the first sub file system by the application to the copy file within the first sub file system by using the file data structure.

14. The apparatus according to claim 11 , wherein the redirecting module is configured to redirect the updates to the file by the application to the first sub file system.

15. The apparatus according to claim 10 , further comprising an application initiator configured to register the ID of the application in a registry, wherein the redirecting module is configured to determine whether the application is a high availability application by determining whether the ID of the application is in the registry, in response to receiving a file access request from the application.

16. The apparatus according to claim 11 , wherein the application is installed respectively on the first sub file system and the second sub file system, and the redirecting modules configured to redirect monitored access operations to a file outside the first sub file system by the application to the first sub file system.

17. The apparatus according to claim 10 , wherein the switching and initiating module comprises: a switching module and an initiating module.

18. The apparatus according to claim 10 , wherein a first sub file system is created on the first node and a storage device shared between the first node and the second node is mounted on the first sub file system, a second sub file system is created on the second node and the storage device is mounted on the second sub file system.

19. The apparatus according to claim 10 , wherein, the monitoring module and the redirecting module are implemented by a file operation hook that is hooked onto file access system calls of the operating system.

20. A non-transitory computer readable storage medium containing computer code that, when executed by a computer, implements a method for realizing high availability of an application installed on a first node and a second node, wherein the method comprises: determining whether an application is a high availability application based on an ID of the application; and performing a file replication process based on a determination that the application is a high availability application, the file replication process comprising: monitoring access operations to files by the application during execution of the application on the first node; and replicating a monitored update to a file by the application based on the application performing an update to the file during the access operations, such replication being from the first node to a storage device accessible by the second node; sniffing execution of the application on the first node; and switching the application to and initiating the application on the second node in response to sniffing a failure in the execution of the application on the first node.